Azure Cost Forecast

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden for behavioral disclosure. It uses the verb 'Retrieves' implying a read-only operation, but does not disclose any other behavioral traits such as auth requirements, rate limits, data latency, or what happens with invalid scopes. It also does not describe the response format or any side effects. This is a significant gap for a tool with no annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences, front-loaded with the primary purpose, and then provides a specific usage scenario with a cross-reference to azure_budget_create. Every word earns its place, with no redundant information or filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The tool has no output schema, so the description should help the agent understand what to expect. It implies the output contains forecast values and enables comparison with budgets, but it does not specify the return structure, granularity behavior, or any limitations. The schema is rich and the use case is clear, but the lack of output details and no annotations leaves the description incomplete for a fully autonomous agent.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the baseline is 3. The tool description itself does not add parameter information, but the schema provides detailed descriptions for all parameters, including scope formats and the CAF tip for mg: scope. The description does not need to compensate further, though it does not enhance parameter understanding either.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states 'Retrieves cost forecasts based on current usage trends' with a specific verb and resource. It also provides a use case (WAF Cost Optimization) and references azure_budget_create. However, it does not explicitly differentiate from sibling tools like azure_cost_query, relying on the tool name and context to imply distinction.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives explicit guidance on when to use this tool: for comparing forecast vs budget to detect overspend risk and for setting budgets with a 100% forecasted threshold to receive early warnings. It also points to azure_budget_create as a complementary tool. While it doesn't state exclusions or alternatives explicitly, the context is clear.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.